<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG April 1999//EN" 
  "http://www.w3.org/Graphics/SVG/svg-19990412.dtd">
<svg width="4in" height="3in">
  <defs>
    <text id="TextToUse">XYZ</text>
  </defs>
  <text>ABC</text>
  <text>
    <src href="#TextToUse"/>
  </text>
</svg>